HB Bibba OR α2136(H19)LEU→PROβ2 in a Caucasian Family from Alabama

Several members of a large Caucasian family who presented with a congenital Heinz body hemolytic anemia were found to be carriers of the unstable Hb Bibba or α2136(H19)Leu→Proβ2. Identification by protein analysis was hampered by the instability of the variant which complicated its isolation from shipped blood samples. Moreover, the detection of the CTG→CCG mutation at codon 136 of the α2 gene required the substitution of dGTP by dITP during the DN A sequencing process to prevent the occurrence of secondary structures and compressions in the sequencing gel. The first Hb Bibba heterozygote, characterized in 1968 (1), is believed to be a member of this family. The clinical expression of the disease is surprisingly variable.